Target detection apparatuses are known as detection apparatuses that are used while mounted to vehicles. Such a target detection apparatus periodically emits radar waves (e.g., laser waves or millimeter waves) as transmission waves, across a predetermined angle around the vehicle, and receives reflected waves to detect various targets present around the vehicle. This type of target detection apparatus is applied to a system that performs vehicle control, such as so-called automatic cruise control (adaptive cruise control (ACC)). Under the automatic cruise control, a vehicle (preceding vehicle) that travels ahead of the own vehicle in the same traffic lane is detected and the vehicle speed is controlled so as to keep an inter-vehicle distance constant, or, when there is no preceding vehicle, the vehicle speed is controlled so as to keep a predetermined constant speed (e.g., see PTL 1).